If the contacts never make or break simultaneouly it's fine.
Even if they do all break at once it's only going to be similar to the bottom circuit but with the resistors replaced by 400Rs rather than 100Rs. These are not precision timing ciruits, they are just arc supressors, so I don't think it will make much difference. Again for safety's sake the single R should be a higher wattage...and I s'pose you'll get some noise cross talk across the circuits.
Do you really want to save 3 Rs that much? It hardly seems worth the effort if it's going to keep you awake at night.
Allow me to exceed my brevquot by regaling you with a tale from yesterday at work.
I'd revised and relaid a circuit board to incorporate some mods and fit in a new housing. Why have I got 0.1uF caps hanging on the gates of my FETs I wondered...don't need them...save a few pence and some circuit board space.
Of course when I built up the first unit the reason for the caps became obvious...whoops...tack 'em on the back of the board.
Fortuantely we'd only had 3 sample boards made anyway...and they need reducing to fit in yet another new enclosure anyhow...whew
Del

Agree - may as well use 4 Rs and 4 Cs. May as well replace the 10nF (C4) with a 0.1μF while he's at it.

I was more curious than interested in saving my R's, though thrift is a virtue. The C values reflect what non-polarized, high voltage caps I have on hand.

Thanks all.